[plug] Hum causing modem dropout

[Greg Gamble]

Hi PLUGgers,

  A colleague experiences the following problem, when he works
at home and tries to connect via modem to uni.

  He has 3 phone points with three phones plugged into them.
One point usually has a T200 phone connected. When the T200 is
connected at this point there is a noticeable hum on the line.
However, when the T200 is swapped for other phones the hum
disappears, and when the T200 is plugged into one of the other
points there is no hum. 
  When the modem is needed it is plugged into the T200's usual
point after disconnecting the T200. However soon after dialling
up via the modem, the modem loses the carrier. We believe it's
due to a hum building up on the line.

  What do you guys think? ... and do you have a possible
solution?

  We believe we can discount any new appliances. Yes, he has
a new VCR ... but his experience is the same with it switched
off and unplugged. Apparently it's not convenient to move the
computer close to another point, to see if the modem dropout
occurs there.

  Regards,
  Greg Gamble <gregg at maths.uwa.edu.au>